Re: [PATCH] iio: adc: sun20i-gpadc: support non-contiguous channel lookups

[Andy Shevchenko <andriy.shevchenko@intel.com>]

On Wed, May 13, 2026 at 11:51:31AM +0200, Michal Piekos wrote:
> Using consumer driver like iio-hwmon which resolve channels thorugh
> io-channels phandles will fail for sparse channels because IIO core
> threats phandle argument as index into channel array.
>         eg. <&gpadc 1> will fail if there is only channel@1 specified
> 
> Add fwnode_xlate which maps DT phandle to the registered channel whose

.fwnode_xlate()

> chan->channel matches the hardware channel number. It allows sparse
> channel maps to be consumed by drivers like iio-hwmon.

...

> +static int sun20i_gpadc_fwnode_xlate(struct iio_dev *indio_dev,
> +		const struct fwnode_reference_args *iiospec)

Broken indentation (I understand the motivation to shift left, but I leave it
to Jonathan on how to proceed with this).

> +{
> +	int i;
> +
> +	for (i = 0; i < indio_dev->num_channels; i++)

	for (unsigned int i = 0; i < indio_dev->num_channels; i++)

> +		if (indio_dev->channels[i].channel == iiospec->args[0])
> +			return i;
> +
> +	return -EINVAL;
> +}

-- 
With Best Regards,
Andy Shevchenko